(A) Procedures shall be utilized to promote improved water quality, and a Postconstruction Storm Water Pollution Prevention Plan shall be submitted to the town for review for each new and redevelopment site. The Plan must include the following information:
(1) A description of potential pollutant sources from the proposed land use that may reasonably be expected to add a significant amount of pollutants to storm water discharges;
(2) Location, dimensions, detailed specifications and construction details of all postconstruction storm water quality measures. Postconstruction storm water quality measures shall be located within platted drainage easements, and adequate access easements or right-of-way shall be provided to allow access to the postconstruction storm water quality measure locations;
(3) A description of measures that will be installed to control pollutants in storm water discharges that will occur after construction activities have been completed. Such practices include infiltration of run-off, flow reduction by use of open vegetated swales and natural depressions, buffer strip and riparian zone preservation, filter strip creation, minimization of land disturbance and surface imperviousness, maximization of open space and storm water detention ponds;
(4) A sequence describing when each postconstruction storm water quality measure will be installed;
(5) Storm water quality measures that will remove or minimize pollutants from storm water run-off;
(6) Storm water quality measures that will be implemented to prevent or minimize adverse impacts to stream and riparian habitat;
(7) An operations and maintenance (O&M) manual that includes a narrative description of the maintenance guidelines for all postconstruction storm water quality measures to facilitate their proper long term function. This O&M manual shall clearly state that the BMP shall be owned by the developer/property owner, and that any and all maintenance and repair activities shall be paid for by the owner. The requirements of the O&M manual shall remain in effect regardless of change in ownership of the development. It shall be the responsibility of the BMP owner to provide the O&M manual to future parties who will assume responsibility for the operation and maintenance of the postconstruction storm water quality measures;
(8) The town or its representatives shall have the right to access the site for inspection of the storm water quality BMP. Any maintenance or repairs that are required as a result of the town’s inspection shall be paid by the owner;
(9) Supporting calculations and documentation demonstrating the adequacy of the selected postconstruction storm water management measures in a report that is signed and stamped by a professional engineer; and
(10) Any other information and provisions required by the town, or as specified in the town standards.
(B) For purposes of establishing a minimum storm water quality treatment level required of new and redevelopment sites, the town’s storm water quality policy shall be based on the reduction of total suspended solids (TSS) through the use of best management practices (BMP). The proposed methodology within the town’s MS4 area shall meet the requirements outlined within Chapters 8 and 9 of the Hendricks County Storm Water Technical Standards Manual. The use of specific BMP described within the Hendricks County Storm Water Technical Standards Manual are required to be approved by the town, and a list of pre-approved (as well as prohibited) BMP will be provided in the town standards. A non pre-approved BMP may be proposed provided that independent, third-party documentation is provided to the town which demonstrates that a minimum treatment level of 80% TSS removal shall be achieved. Regardless of the BMP utilized, each site shall incorporate methods to capture floatables (oils, debris and the like).
(C) Where appropriate, any combination of storage, infiltration, filtering or vegetative practices shall be used to reduce the impact of pollutants in storm water run-off on receiving waters. In addition to the combination of practices, the following requirements shall be utilized:
(1) Infiltration practices will not be allowed in wellhead protection areas;
(2) Discharges from an MS4 area will not be allowed directly into sinkholes or fractured bedrock without treatment that results in the discharge meeting state ground water quality standards as referenced in 327 I.A.C. 2-11.
(3) Any storm water practice that is a Class V injection well must ensure that the discharge from such practices meets state ground water quality standards as referenced in 327 I.A.C. 2-11;
(4) As site conditions allow, the rate at which water flows through the MS4 conveyances shall be regulated to reduce outfall scouring and stream bank erosion;
(5) As site conditions allow, a vegetated filter strip of appropriate width shall be maintained along unvegetated swales and ditches; and
(6) New retail gasoline outlets, new municipal, state, federal or institutional refueling areas, or outlets and refueling areas that replace their existing tank systems shall be required to design and install appropriate practices to reduce lead, copper, zinc and polyaromatic hydrocarbons in storm water run-off.
(Ord. 33-2006, passed 10-9-2006)